Autonomous Technology vs Minnesota Winter: The Superbowl Challenge

By Bob Filipczak

The testing of autonomous vehicles has been in the news a lot, and each article makes new claims about what these vehicles can do. If there’s some skepticism among engineers in northern states such as Minnesota, it makes sense. We all want to know if this technology can stand up to the trifecta of snow, ice and salt when it comes to navigating our roads.

As part of a demonstration during the Superbowl festivities, an autonomous bus is going to do six days of transporting folks around downtown Minneapolis. This bus just needs to pass a few tests first, explains Michael Kronzer, ITS project manager for the Office of Traffic Safety Technology at MnDOT.

These tests will occur at MnROAD, MnDOT’s testing and research facility in Monticello, MN. A stone’s throw from I-94, MnROAD has a closed test track where it usually runs a fully-loaded 18-wheeler about 8 hours a day to see how the different pavements hold up. The track will be repurposed for a few days in December to test the autonomous bus.

This bus will be sporting three different kinds of sensors plus a GPS system, explains Kronzer. It will have cameras, a radar system and a LiDAR unit. The multiple sensors are to create redundancy in the whole system to maximize safety. The technology is well established, but getting the sensors to talk to each other can be tricky. “It’s going to be more of a challenge to figure out how the multiple parts of the technology will compensate when one sensor is not able to do its job,” says Kronzer.

So in this corner we have a high-tech, autonomous bus outfitted with redundant sensors communicating with one another. In the opposite corner, we have a Minnesota winter featuring snow, ice, salt and cold that can intimidate the most courageous traveler. It should be mentioned at this point that, to Kronzer’s knowledge, this kind of testing has never been tried before. Some testing has been done in cold situations, but not with snow, ice and salt.

Nevertheless, Kronzer is confident. “The industry is aware of the challenges and they are ready for the winter conditions—snow, ice and salt,” he says.

Of the three sensors, the LiDAR is the most likely to face the toughest time, says Kronzer. The snowflakes in the air could confound its capabilities, as well as the salt on the road.

If it’s true that Minnesota winters are tough, it’s also true that they are unpredictable, and the MnDOT team had to admit early on that no one could guarantee the testing conditions necessary. Consequently they contracted with Powder Ridge ski area in Kimball, MN in case they needed to create their own “conditions.” They will have some snow machines ready when the testing begins. Kronzer says, however, that ambient snow conditions are ideal.

One other factor in these tests may be the vehicle itself. It’s completely electric, and they are not sure how cold will affect the longevity of the battery when it faces the chilly ferocity of a Minnesota February.

So if the bus passes the tests, what then? It will become a demonstration project of the technology during Superbowl 52 in Minneapolis. It will be open to the public and will run on a predetermined route.

There will be an operator aboard who can interrupt things if safety becomes a concern. In addition, even though the bus will have proven it’s mettle against snow, ice and salt, it will only run if the weather is conducive to safety. That means, says Kronzer, it will not run if there is ice, slush or snow on the route.